Sewer grate with insect block

ABSTRACT

A water sewer drainage system particularly directed to prevent spread of West Nile disease includes an underground water drain off region, a ground level opening to a down passage to the drain off region, a sewer grate across the ground level opening and an insect block in the down passage below the sewer grate. The insect block inhibits insects from gaining access to the drain off region while permitting flow of water through the system.

FIELD OF THE INVENTION

[0001] The present invention relates to a water sewer drainage system including an insect block to inhibit insects such as mosquitoes and the like from gaining access to the drain off region of the system which may at different times contain trapped stagnant water.

BACKGROUND OF THE INVENTION

[0002] West Nile disease, which is a disease transmitted by mosquitoes is becoming an ever increasing threat. Mosquitoes typically inhabit stagnant water. One such potential area i.e., habitation ground for the mosquito infestation is within a storm sewer where non-running water will collect beneath ground surface. This non-running water then provides a stagnant breeding ground for mosquitoes. As will be understood the particular problem presented by storm sewers is that they are generally located in highly populated locations where people are easily accessible to mosquito bites.

SUMMARY OF THE PRESENT INVENTION

[0003] The present invention provides a sewer drainage system specifically designed to inhibit mosquitoes populating the under ground run off region of the system.

[0004] More particularly, according to the present invention a sewer drainage system includes an under ground water drain off region, a ground level opening to a down passage to the drain off region, a sewer grate across the ground level opening and an insect block in the down passage below the sewer grate. The insect block inhibits insects such as mosquitoes and the like from gaining access to the drain off region while permitting flow of water through the system.

[0005] According to an aspect of the present invention, the insect block comprises a rigid flap which is pivotally held within the system biased to normally assume a down passage blocking position. The flap when exposed to the pressure of water flow on the flap is movable by the pressure to a down passage opening position. When there is no water flow on the flap it is urged back to its passage blocking position.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The above as well as other advantages and features of the present invention will be described in greater detail according to the preferred embodiments of the present invention in which;

[0007]FIG. 1 is a perspective view looking down on a water sewer drainage system according to a preferred embodiment of the present invention;

[0008]FIG. 2 is a sectional view through an upper region of the system of FIG. 1 with the grate being swung away from its normal use position;

[0009]FIG. 3 is a perspective view looking down on a sewer drainage system according to a further preferred embodiment of the present invention;

[0010]FIG. 4 is a sectional view through the system of FIG. 3 showing different operating positions of the flap of that system;

[0011]FIG. 5 is a perspective view of a down passage blocking flap of a sewer drainage system according to further preferred embodiment of the present invention; and

[0012]FIG. 6 is a sectional view of a sewer drainage system incorporating the flap of FIG. 5.

DETAILED DESCRIPTION ACCORDING TO THE PREFERRED EMBODIMENTS OF THE PRESENT INVENTION IN WHICH

[0013]FIG. 1 shows a sewer drainage system generally indicated at 1 according to a first preferred embodiment of the present invention. This system incorporates features of known storm sewer systems which are typically found in a roadway 7 bordered by a sidewalk 3 and a curb 5. The system shown in FIG. 1 includes a sewer grate 9 held in position by a grate frame 11 over a down passage 13 which leads to a water run off region defined by sewer drain pipe 15. In many instances, the drain pipe will not completely clear leaving a small puddling of water 17 in the drain pipe. Over extended periods of time when there is no rainfall this water has the potential of becoming a stagnant breeding area for bugs such as mosquitoes and the like.

[0014]FIG. 2 of the drawings shows that system 1 according to the present invention further includes an insect block generally indicated at 21. When there is no water flowing into the system the block 21 assumes a blocking position within the down passage 13 to inhibit insects from entering the system as far as the drain pipe. Under water flow conditions such as those experienced during a rainy period insect block 21 allows movement of water through the system. At such times there is essentially no likelihood that flying insects such as mosquitoes will even attempt to enter the system particularly in view of the fact moving water has a tendency to trap and kill such flying insects. As such, it is only during dry conditions when the system is not exposed to flowing water that insect breeding becomes a potential hazard. As earlier noted, under these particular conditions block 21 inhibits the insects from entering the drain system.

[0015] Turning now to further details of the system it will be seen that insect block 21 comprises a pair of preferably rigid flaps 25 and 31. Flap 25 is pivotally secured at 27 to a frame 23. Flap 31 is pivotally secured at 33 to this same frame.

[0016] The insect block frame 27 has an L-shaped configuration in which the horizontal leg of the frame seats on the grate frame 11. The pivot mounts 27 and 33 for the two flaps are provided on the down leg of frame 23. Provided beneath flap 25 is a flexible spring steel member 29 which is secured between the under surface of flap 25 and the inside surface of the down leg of the frame 23. A similar spring steel member 35 is provided beneath flap 31.

[0017] The two spring steel members 29 and 35 normally hold flaps 25 and 31 in the dotted horizontal position of FIG. 2. In this position the two flaps completely block down passage 13 beneath the sewer grate. Also in this position the flap prevent bugs and insects and in particular flying insects such as mosquitoes from moving through the down passage to any stagnant water which may be trapped in drain pipe 15.

[0018] When the sewer system is put to use for water drainage the weight of any water flowing onto the two flaps will automatically push them downwardly to their solid line open positions shown in FIG. 2. In these positions the water is allowed to flow past the block through the down passage 13 to the drain pipe 15. As described above under these conditions there is essentially no concern that flying bugs will successfully enter the drain system with the water.

[0019] As soon as the water flow onto the flaps ceases the spring steel members 29 and 35 will push the flaps 25 and 31 back to their respective blocking positions.

[0020] Also included in the FIG. 2 setup is a movement control bar 35 between the two flaps 25 and 31. This bar while not inhibiting the flaps to move between their open and closed positions does prevent either flap from being pushed downwardly beyond a desired open position in which the flaps might have difficultly returning to their closed positions. Accordingly bar 35 is a movement limit control bar for both of the flaps.

[0021] A particular feature which should be noted with respect to the system of FIG. 2 is that with grate member 9 swung away from its sewer covering position the entire insect block 21 including both the frame 23 and all the components attached to the frame can be easily pulled out of the sewer system. This enables easy inspection and/or maintenance of the insect block. It further allows workers to enter the system down to the drainage pipe using the hand rails 14 on the down passage wall by simply raising the grate and pulling the insect block out of the system. After the workers have completed their inspection the insect block is simply dropped back into its operating position.

[0022]FIG. 3 shows a drainage system generally indicated at 41 according to another preferred embodiment of the present invention. This system once again incorporates a grate 45 held in position by a grate frame 47 over a down passage 43. Down passage 43 leads to a sewer pipe which is not shown in FIG. 3.

[0023] Provided beneath grate 45 is an insect block generally indicated at 49. This insect block is in the form of an angled plate formed by first and second plate or flap parts 51 and 53 meeting at a center apex defined by a pivot bar 55. Pivot bar 55 is mounted directly to the walls of the down passage.

[0024] In this particular embodiment the two flaps are of identical weight and are set at identical downward angles relative to the center apex of the overall plate or flap construction. As such, under normal conditions when there is no water entering the system the plate will hang in the solid line position of FIG. 4. In this position, it blocks insect access past the plate down the passage 43. It holds this position because of the balanced weight and design to either side of the pivot mount.

[0025] As soon as water flows into the system, the weight of the water causes the insect block to move to an open position within the down passage 43. The dotted line configuration of the plate shown in FIG. 4 is one such open position where the water is allowed to flow past flap part 51 pushed downwardly away from the wall of the down passage under the weight of the water.

[0026] The plate might just as easily be pushed downwardly on the flap side 53. However, it will never be the case that water falling on the plate will divide completely evenly to both sides of the plate and as such the plate will always have a tendency to open under the weight of water.

[0027] As soon as the water flow onto the plate is discontinued the balanced construction of the plate will once again urge it back to the passage closed position.

[0028]FIGS. 5 and 6 of the drawings show another embodiment of the invention. In this embodiment a drainage system 61 includes a grate 63 positioned above a down passage 64. An insect block generally indicated at 65 shown in FIG. 5 of the drawings is provided within down passage 64.

[0029] Insect block 65 comprises a flap or plate 67 which is free at one end to move within the passage as shown in the left hand side of FIG. 6. The other end of the flap includes a bar 71 which fits at its opposite ends into a pair of flap mounts 69. These flap mounts which secure directly into the wall of the down passage 64 are fitted with springs such as coil springs or the like. These springs normally hold flap 67 in the horizontal solid line insect blocking position of FIG. 6.

[0030] When the system is exposed to water flow the weight of the water will push flap 67 down to the dotted line position of FIG. 6 to allow the water to flow through the system. Once the water flow has stopped the spring tensioning within mounts 69 will pull the flap back up to the FIG. 6 solid line position.

[0031] As will be appreciated from the description above there are numerous different designs including designs which may or may not include spring assists to normally urge the insect block to a blocking position. As such, it is to be appreciated by those skilled in the art that variations of the embodiments described above are to be included as part of the invention and within the scope of the appended claims. 

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
 1. A sewer drainage system, said system including an underground water drain off region, a ground level opening to a down passage to said drain off region, a sewer grate across said ground level opening and an insect block in said down passage below said sewer grate, said insect block inhibiting insects from gaining access to said drain off region while permitting flow of water through said system.
 2. A sewer drainage system as claimed in claim 1 wherein said insect block comprises a rigid flap which is pivotally held within said system, said flap being biased to normally assume a down passage blocking position and said flap when exposed to water flow thereon being moved to a down passage opening position.
 3. A sewer drainage system as claimed in claim 2 including a pivot mount at one end of said flap for pivotally securing said flap within said down passage of said system, said pivot mount including a spring which biases said flap to the down passage blocking position.
 4. A sewer drainage system as claimed in claim 2 wherein said flap includes first and second flap parts fixedly held with one another at a pivot mount of said flap, said flap parts being balanced to opposite sides of said pivot mount to urge said flap to the down passage blocking position.
 5. A sewer drainage system as claimed in claim 4 wherein said flap has an angled configuration with an apex at said pivot mount and said first and second flap parts being angled downwardly to opposite sides of said apex of said flap.
 6. A sewer drainage system as claimed in claim 2 wherein said sewer grate comprises a grate frame surrounding said ground level opening, and a grate member which is pivotally mounted to said grate frame for swinging said grate member to and away from the down passage covering position, said system including a flap mounting frame to which said flap is pivotally mounted, said flap mounting frame seating on said grate frame and being sandwiched between said grate member and said grate frame when said grate member is in the covering position, said flap frame and said flap, being liftable from said system when said grate member is away from the covering position. 